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Hello I have a 1960 C60 viking with a 2 speed rear end my problem is the rear brakes wheel cylinders are leaking I have replaced on side with no problem but the othe side there is a steel line that connects the 2 wheel cylinders started leaking and thinking no big deal I tossed the line and befor I realized how much trouble it would be to find a relacement the old is gone and the new will not screw in because of the diffrent thread pitch and I can not find the correct thread pitch can anyone help

should be standard hard line threads. Very hard to line up and easy to strip, don't ask! Did yours also have square block to screw into, or just into cylinders? My GMC had line on outside of back plate, but have had some inside too. Biggest problem is the fancy bends orig had at ends before nut, can't make them in shop. On my outside ones, I got new blocks with the bolts with holes to cylinder, and my brake shop can now make hoses with common fittings. I had small hose made up and it allows you to move around easier to align the nuts. Try around you for a brake wholesaler/service shop. One in my area is great with parts and knowledge on old trucks, rarely lets me down. I figure if they don't have it, it's not made or sold anymore.

1960C60Viking

I'am also working on my rear breaks. I twisted
the line and have not started to look for a new one yet. Was you able to buy a new line for it or did you have someone make one for you.
Someone might have worked on it befor you and striped the threads in the wheel cylinder You might want to try it on another cylinder that you know is good
Did you rebuild your wheel cylinders. I have found a place where I can get a wheel cylinders kit for $14.00. Mine are a little pited. But I think I can clean them up enough to reuse them.
If you come up with any information on this let me know. Going to take the master cyinder off today
Bruce j

I bought all new wheel cylinders at my Local NAPA store and the guy there said "I've been doing this for 20 years and have never seen anything like that" refering to the 7/16 x20 threads in the wheel cylinders for the crossover tube. if you have the two nuts off of the line you can make a new line with them. thats where I am having trouble i threw my away thinking no big deal I just get a new one. and by the time I relized I needed the old line for the nuts it was already to late .. and as for the pitting I thought that to just hone them out and put in new parts NOT this is the fourth time taking them all apart and putting them back toghter again ,,, those duals are getting heavy... and we put on new tires 8.25x20 on the old 2 pc wheels (widow makers) next is the front brakes

GLPerry my wheel cylinders have a block on the back that the hard line screws into the block is screwed into the wheel cyl with a banjo bolt into the lower/back cyl then out of it through the crossover tube to the front/upper wheel cyl then that one is the one you bleed since it is the highest point for that wheel. and the old and new wheels cyl all have this diffrent thread for the crossover tube to screw into. I thought standard steel line so standard threads.. "NO WAY" and dont try screwing a regular line in them and altering the threads.. (it breaks the wheel cyl housing) so would anyone care to look around at where ever and find some new or a old used line with good nuts in a 7/16x20 threads....PLEASE

Hy guys, I'm getting confused, in my experience 7/16 x 20 tpi is the thread pitch for the banjo bolt type of attachment an no line seat inside that bore. 7/16 x 24 tpi is the standard thread pitch for 1/4 brake line. Are you saying that there is a hole in your cylinders with a seat and 7/16 20 tpi? If that is the case I've never encountered it before please clarify.

Yes that is what I am saying 7/16 x 20 with a seat is what I have for my cross over tube threads

Hy 1960C60Viking according to my books your truck has a bendix brake system, I can find a number for the wagner crossover line but not for the bendix system. Try this fix instead weatherhead makes an adapter to go from 7/16" x 20 T.P.I. to female 1/4" inverted flare, that would allow you to make up your crossover line out of standard 1/4" brake line the part number is 7732 this fitting seals on its hex not on a seat so you might want to purchase the appropriate copper washer as added insurance for a good seal. Hope this does the trick for you.

Thanks 3B I have already done that but the copper washer willnot seal correctly because of the rough casting of the wheel cyl I took a dull drill bit and tapered the brass adapter to make a taper seal I hope it works (dont try a sharp bit brass is very soft..grabs and tears out big chunks) will put it all together tomarrow,, and Thanks again

Hy 1960C60Viking Glad to see you got it all back together, the seats in most cylinders are supposed to be removable, they have to be machined and I guess you can't do that down that little hole. Don't ask me how it is retained in there I've never had to remove one, but it is an interesting little fact to remember for future reference.

http://www.americanclassic.com/Google_Base_HTML_Pages/BR4401.htm

i know this is an old thread but I am researching what looks like the same problem of getting brake line fittings to fit properly to rear brake wheel cylinders. This adapter looks like it is what I being searching for.